CN113508025A

CN113508025A - 3D printing apparatus for applying printing material with temperature adjustment device

Info

Publication number: CN113508025A
Application number: CN202080016695.6A
Authority: CN
Inventors: 斯特凡·贝茨; 克莱门斯·利伯沃思; 文森特·莫里森
Original assignee: Em 3d Co ltd; Bozewalsburg Automotive Parts Europe
Current assignee: Em 3d Co ltd; Bozewalsburg Automotive Parts Europe
Priority date: 2019-03-05
Filing date: 2020-03-04
Publication date: 2021-10-15
Also published as: WO2020178335A1; EP3934888A1; JP2022522877A; US20220134662A1; DE102019202942A1; EP3934888B1; US11993019B2; EP3934888C0

Abstract

The proposed solution relates in particular to a 3D printing device having at least one printing nozzle (10) for applying printing material (50, 51) arranged for producing a component to be printed in layers along an application direction (R). The 3D printing device (1) has a temperature control device (4) which is set up and arranged for cooling and heating the printing material (50, 51) which has been applied, for example via a plurality of annular carriers (41, 42, 43) each having a plurality of outflow openings (41a-41e, 42a-42e, 43a-43e), in the region of the printing nozzle (10).

Description

3D printing apparatus for applying printing material with temperature adjustment device

Technical Field

The proposed solution relates to a 3D printing device with at least one printing nozzle for the layered application of printing material for the manufacture of a component to be printed.

Background

In 3D printing, three-dimensional structures are typically built up in layers of one or more materials. Here, for example, plastics, resins, ceramics and/or metals are used as materials. For example, in this regard, a so-called melt layer method or Fused Deposition Modeling method (English: "Fused Deposition Modeling", abbreviated as FDM) is known. In this case, the component or the workpiece is constructed in layers from a meltable plastic or a meltable material.

In order to produce the respective components in layers, the printing material is applied to the printing plate in one application direction (of a plurality of possible application directions) via at least one printing nozzle of a printing device, for example in the form of a so-called 3D printer. In this case, the individual components are built up in layers by the printing material escaping at the printing nozzles, using computer assistance.

In this respect, it is known, for example, from WO 2018/039261 a1 to pre-warm a first layer of printing material which is located in the application direction and has already been applied and then apply a further second layer of printing material via the printing nozzles. The corresponding preliminary warming of the already applied printing material layer is used here to improve the adhesion of the newly applied printing material to the already existing layer. WO 2018/039261 a1 describes here, for example, the heating of already previously applied printing material in the application direction using a laser or hot air stream.

Disclosure of Invention

On this background, the task of the proposed solution is to further improve the 3D printing device.

This task is solved with a 3D printing device according to claim 1 and a 3D printing device according to claim 13.

According to a first aspect, the proposed solution provides for the 3D printing device to have a temperature control device which is set up and arranged for cooling and heating the already applied printing material in the region of the printing nozzles. Thus, if desired, the printing material present in the environment and thus located, for example, locally below the printing nozzles can be cooled or heated via the temperature-regulating device.

The proposed solution comprises in particular the following variant in which the printing material, for example, in the application direction is heated in order to improve the adhesion of the subsequently applied printing material. In this respect, it can be ensured, for example, that the already applied printing material is set to a temperature at which it can be connected, and/or that (in particular in the case of a material filled with glass fibers) the already applied printing material can still be heated to such an extent that the printing material newly applied from the printing nozzle can then penetrate into the already applied printing material. With the proposed temperature control device, it is also possible to cool the printing material that was previously applied by the printing nozzle only once, for example when using different printing materials in different production runs with the same 3D printing device or for forming specific, in particular thin-walled sections of the component to be printed, or simultaneously with heating the printing material. This cooling is used, for example, to prevent the applied printing material from running off or melting and to support the hardening of the printing material. It can also be provided that the switching between cooling and heating takes place in the region of the printing nozzle, depending on the build-up time of the printing material of the current layer and/or depending on the section of the component to be produced, for example a bridge or a cantilever.

Thus, flexibility in manufacturing a three-dimensional component to be printed can in principle be increased via the proposed 3D printing device.

Accordingly, the temperature-regulating device can be set up and set up, for example, for heating an already applied printing material in the application direction, onto which a new printing material is to be applied by means of the nozzle. The temperature control device is therefore designed and arranged to heat the already applied printing material when a new printing material is applied to it by the printing nozzle.

Furthermore, the temperature regulation device can be set up and provided for cooling a printing material applied by the printing nozzle, which printing material has been applied by the printing nozzle in advance. The printing material can thus be cooled by the temperature-regulating device after it has been applied by the nozzle and, if necessary, during the time when the printing nozzle continues to be adjusted in the application direction for applying a new layer of printing material. In one embodiment, the fluid flow for cooling can thus be generated, for example, by means of a temperature control device in the direction of the printing material just applied by the printing nozzle. The cooled fluid is blown out via the temperature control device in the direction of the printing material that has just been applied by the printing nozzle.

In principle, at least one fluid flow with heated or cooled fluid can be generated via the temperature regulation device for heating and/or cooling the applied printing material. In particular, it can be provided that the fluid heated or cooled can be used for the fluid flow in a selective manner via the temperature control device, and for example, a different fluid reservoir is provided for this purpose, or the temperature control device has at least one heating and cooling element in order to heat or cool the fluid to be blown off in a targeted manner.

In one possible refinement, the temperature control device has at least one carrier with at least one outflow opening for the fluid. The respective carrier thus defines a fluid path for the fluid flow to be generated, so that the fluid flow at the at least one outflow opening of the carrier is directed in the direction of the printing material to be cooled or heated. The at least one carrier may be arranged at least partially in the region of the printing nozzle, so that the fluid flowing out of the at least one outflow opening is brought to converge on the already printed printing material in the immediate vicinity of the printing nozzle.

In an embodiment variant, provision is made, for example, for at least one carrier to have at least one first outflow opening for generating a fluid flow provided for heating the printing material and at least one second outflow opening for generating a fluid flow provided for cooling the printing material. In this connection, it is thus possible for different outflow openings to be present on at least one carrier, to which, depending on the application, heated or cooled fluid is supplied. Of course, the at least one outflow opening of the carrier can also be set up and arranged for allowing different fluids and/or one fluid having a different temperature to flow out through them.

Alternatively or additionally, the at least two carriers may be part of a temperature regulation device. In this case, different carriers can also be provided on the 3D printing device for generating different fluid flows and/or for different fluids. Depending on what type of fluid flow (in terms of temperature and/or outflow direction) or what type of fluid, in particular what type of gas, is to be discharged in a targeted manner, for example, one or other carrier can be used.

In one embodiment, the temperature control device has at least one valve, in particular a multi-way valve, for controlling the inflow of different fluids and/or for controlling the inflow of fluids via different fluid paths. In the latter variant, the temperature regulation device provides different fluid paths, for example in order to allow heated fluid to flow through the first fluid path and cooled fluid to flow through the second fluid path and finally to be directed in the direction of the applied printing material. The inflow can be adjusted accordingly via at least one valve, so that one fluid path cannot be used, while another fluid path is available, for example, depending on the position of the valve.

In particular, the temperature regulation device with at least one valve can be set up and arranged for controlling the inflow of heated fluid via a different fluid path than the inflow of cooled fluid. Via at least one valve, for example, it is possible here to control: to which carrier or carriers of a plurality of different carriers the fluid flows and/or to which outflow opening of the carrier the fluid flows. The supply of fluid to which carrier and/or which outflow opening is provided can in this case depend in particular on which fluid is to be used and/or whether the fluid is provided for heating or cooling.

As an alternative or in addition to the generation of the fluid flow, the temperature regulation device may have at least one emitter for heating the printing material that has been applied. Such emitters comprise, for example, lasers, LEDs or infrared radiators, via which the printing material can be heated locally in the region of the printing nozzles via radiant heat.

In principle, the temperature-regulating device can be electronically coupled with the at least one sensor device in order to control the degree of heating or cooling (and thus for example the temperature of the fluid utilized or the amount of radiant heat emitted by a possible emitter) electronically (and thus at least partially or fully automatically) in dependence on the at least one sensor signal, which is an indication of the temperature of the printing material to be heated or cooled.

The at least one sensor device may comprise, for example, one or more thermal imaging cameras, the image data of which are evaluated with the aid of a computer for calculating the printing material temperature and are used to generate sensor signals. Alternatively or additionally, one or more movable sensors can be provided, which can be adjusted directly on the nozzle head in an electronically controlled manner. Alternatively or additionally, a fixed or only slightly adjustable sensor can be provided in the region of the nozzle head, which sensor can detect the temperature of the applied printing material by means of a movably mounted and electronically controlled adjustable mirror.

In one embodiment variant, the temperature regulation device has control electronics which are configured to control the heating or cooling in dependence on the application direction to which the printing nozzle is adjusted. In such an embodiment variant, it can therefore be varied whether the printing material in the vicinity of the printing nozzle is heated or cooled via the temperature-regulating device and/or whether only a part of the temperature-regulating device is used for heating or cooling and which part is used for heating or cooling, depending on which of a plurality of possible application directions the printing nozzle is adjusted to exactly with respect to the printing platform. If the temperature regulation device has, for example, a plurality of carriers and a plurality of outflow openings, the control electronics are, for example, configured to supply fluid only to the carriers and thus only to the outflow openings via which a fluid flow can be generated (in the application direction) before the printing nozzles for heating the printing material or via which a fluid flow can be generated (opposite to the application direction) after the printing nozzles for cooling the printing material.

In one variant, the control electronics are configured, for example, to control the heating or cooling in dependence on the application direction by: the carrier (e.g. the annular nozzle) that can be adjusted is rotated in a targeted manner with respect to the application direction (i.e. the printing path) by the control electronics. In this way, the cooling jet can be always oriented towards the rear of the print or backwards with respect to the application direction in order to cool the printing material just applied. At the same time, the heat source may be forward and thus directed in the application direction in order to heat the area where the printing material is to be applied.

Another aspect of the proposed solution relates to a 3D printing apparatus with a temperature regulating device comprising a plurality of temperature regulating elements for cooling an already applied printing material and/or a plurality of temperature regulating elements for heating an already applied printing material, wherein the temperature regulating elements are arranged on a section of a carrier of the temperature regulating device extending at least partially around a printing nozzle.

The temperature-regulating element can be, for example, an emitter for heating the printing material that has been applied, and thus, for example, a laser, an LED and/or an infrared radiator. Temperature control elements are also understood to be outlet openings for a fluid flow with a heated, in particular warmed, fluid or with a fluid that is cooled.

In the 3D printing device proposed according to the second aspect, the respective temperature regulating element is located on a section of the carrier which extends at least partially around the printing nozzle and thus covers a defined area along the circumference of the printing nozzle for locally heating or cooling the printing material. For example, the carrier can be formed to extend in a circular arc or ring shape around the printing nozzle. The section of the carrier with the temperature control element which extends at least partially around the printing nozzle can therefore follow the course of a circular line around the printing nozzle.

In one embodiment variant, the temperature control device has control electronics which are configured to utilize different temperature control elements depending on which application direction the printing nozzle is adjusted to. This includes, for example, that the control electronics are configured to utilize only one or only some of the plurality of temperature-regulating elements, depending on the application direction, in order to heat or cool the printing material in a targeted manner (for example with respect to the application direction) before or after the printing nozzle.

The temperature control element can also be located on a different carrier, which simultaneously forms, for example, a flow generating element, such as an annular nozzle, which surrounds the printing nozzle.

The two aspects of the 3D printing device discussed above may of course also be implemented in a single 3D printing device.

Drawings

The figures exemplarily illustrate possible implementation variants of the proposed solution.

Wherein:

fig. 1 shows a first embodiment variant of the proposed 3D printing device in a section from the perspective of a printing nozzle, on which an annularly encircling carrier with a plurality of temperature control elements for cooling or heating the applied printing material as required is arranged;

fig. 2 shows a further embodiment variant of the proposed 3D printing device, which has two concentric, annular carriers with optional valve controls for temperature control elements configured as outflow openings on the carriers;

fig. 3 shows a further embodiment variant of the proposed 3D printing device in a view corresponding to fig. 1 and 2, with three carriers arranged concentrically to one another, each being annular;

fig. 4 shows schematically and in sections a 3D printing device which can be equipped with a printing nozzle according to one of fig. 1, 2 or 3, and schematically illustrates a sensing means coupled to a corresponding thermostat.

Detailed Description

Fig. 4 schematically shows a 3D printing device 1 with a printing nozzle 10 via which printing material can be applied onto a printing platform 2 for layerwise building up of a part or workpiece. The printing nozzle 10 is here exemplarily adjusted along the application direction R.

In the variant shown in fig. 4, a layer of printing material 50 is already present on the printing platform, and a second layer of printing material 51 is applied to this first layer of printing material by means of the printing nozzle 10. The 3D printing device shown here operates, for example, according to the melt layer method or the Fused Deposition Modeling method (in english: "Fused Deposition Modeling", abbreviated to FDM). As the printing material 50 is applied on the printing platform 2 for the first time, cooling of the applied printing material 50 is started at the same time, so that when the print head and the print nozzles 10 of the 3D printing device 1 come to the same position again, the previously applied printing material 50 is much cooler than the new printing material 51 to be applied. This can have a negative effect on the connection of the two strands and the strength of the component manufactured therewith.

Against this background, the embodiment variant of fig. 4 provides for the printing material 50 of the previously applied layer 50 in the application direction R to be heated locally via the laser 4 a. By this local heating by means of the laser 4a (or other emitter, for example an infrared radiator, or by means of a fluid flow with heated fluid) and the associated energy input into the printing material 50, the already applied printing material 50 is heated, after which a new printing material 51 is applied thereto. Thereby, the adhesion of the newly applied printing material 51 on the previously applied printing material 50 can be improved. In this way, a mixed printing method can also be carried out more efficiently, in which the plastic material is printed with metal powder. By targeted heat input, it is possible here to subsequently melt the printed metal powder in order to form a metal structure, for example in the form of at least one conductor track, for example within the printed plastic.

Via a sensor device 3 coupled to a temperature regulation device 4 with a laser 4a and having one or more sensor devices, the energy input into the already applied printing material 50 is controlled in dependence on the known temperature of the printing material 50. The sensor device 3 here comprises, for example, an optical measuring device and/or at least one temperature sensor. For example, as an alternative or in addition to the temperature sensor, the sensor device 3 comprises one or more thermal imaging cameras and is configured to calculate the temperature of the printing material 50 in the region of the printing nozzle 10 with the aid of a computer and to drive the laser 4a in dependence on this temperature known with the aid of a computer.

In the embodiment variant according to fig. 1, an annularly encircling carrier 41 is provided in the region of the printing nozzle 10. The annular support 41 is part of a temperature control device 4, via which a first layer of printing material 50 applied in a preceding cycle can be heated in a targeted manner and/or via which a subsequent layer of printing material 51 just applied to this layer can be cooled in a targeted manner.

For this purpose, a plurality of temperature control elements 41a to 41e are spaced apart from one another on the carrier 41, in particular are spaced apart from one another at equal distances and are distributed over the outer circumference of the annular carrier 41. Each temperature control element 41a to 41e can be formed here by an emitter for generating radiant heat or by an outflow opening for the fluid, so that the carrier 41 can be configured in particular as an emitter ring or annular nozzle. Depending on whether the

printing material

50, 51 is to be cooled or heated for the layered application of a new printing material 51 and in which application direction R the printing nozzle 10 is adjusted, only a single one of the temperature-regulating elements 41a to 41e or only a part of the temperature-regulating elements 41a to 41e is activated.

If a plurality of outflow openings 41a to 41e are provided, for example, distributed over the circumferential side of the annular support, the heated fluid can flow out, for example, from the

outflow openings

41d and 41e in the application direction R, in order to heat, in particular to pre-warm, the printing material 50 of the already existing layer before and below the printing nozzle 10 locally and then to bring the printing material 51 spread out at the printing nozzle 10 for the subsequent layer into contact with this printing material 50. Alternatively or additionally, the cooling fluid may flow out from the

outflow openings

41a, 41b located opposite to the application direction R, so that a flow of cooling fluid may be generated in the direction of the just applied printing material 51, in order to prevent the printing material 51 from melting. Thus, with the illustrated temperature regulating device 4, the applied

printing material

50, 51 can be selectively heated or actively warmed or cooled. Depending on the build time of the current layer and/or depending on the component section to be produced, it is possible to specifically control: whether it is heating or cooling and should especially be in which direction and at which position/positions along the circumference of the print nozzle 10 a fluid flow is generated.

For automation, the thermostat 4 comprises control electronics 40. The control electronics 40 can then, for example, also be coupled to the sensor device 3 in order to control the extent of heating and/or cooling depending on what temperature the

respective printing material

50 or 51 has.

In one variant, the control electronics 40 are configured to control the heating or cooling depending on the application direction by: the carrier 41 is mounted so as to be rotatable about the printing nozzle 10d and can be rotated in a targeted manner with respect to the application direction (i.e. the printing path) by means of the control electronics. In this way, the cooling jet can always be oriented backwards with respect to the application direction in order to cool the printing material just applied. At the same time, the heating may be directed in the direction of application so as to heat the area to which the printing material is to be applied. Alternatively or additionally, the outflow openings 41a to 41e can be closed and opened in an electronically controlled manner in a targeted manner individually or in groups via valves, in particular piezoelectric valves, in order to be able to orient the cooling and/or heating in a targeted manner, in particular in dependence on the current application direction of the printing material and thus the printing path.

Instead of a single carrier 41, the variant embodiment of fig. 2 is provided with two

annular carriers

41 and 42 of the temperature-regulating device 4 extending concentrically with one another around the printing nozzle 10. In this case, for example, only a fluid flow for heating the printing material 50 is generated via the inner carrier 41 and its outflow openings 41a to 41 e. Correspondingly, a fluid flow with the fluid to be cooled is generated via the outlet openings 42a to 42e of the outer carrier 42. For example, the same fluid, e.g. air, is involved in both cases. The air can be conveyed to one carrier 41 or the other carrier 42, optionally heated or unheated or even additionally cooled, depending on whether the air is to be used for heating or cooling and via which

carrier

41, 42 the air is to be blown out. For example, air is provided via a compressed air interface.

For controlling the inflow to the

carriers

41, 42, a valve control with at least one (multi-) valve 400 may optionally be present. The valve 400 is then also controlled via the control electronics 40 of the thermostat 4.

In the embodiment variant of fig. 3, three

annular carriers

41, 42 and 43 are provided, which extend concentrically around the printing nozzle 10. Via the additional outer annular carrier 43 with the outflow openings 43a to 43e, for example, it is possible to discharge, in addition to hot and cold air, if required, alternative process gases. Such process gases for cooling and/or for heating can be used, for example, when reactive printing materials are to be printed, such as carbon fiber-reinforced plastics, glass fiber-reinforced plastics or special metal powders or joining means, which cause undesirable oxidation when cooled or heated with air.

In each of the embodiments shown in fig. 1, 2 and 3, the temperature-regulating device 4 can have suitable heating and/or cooling elements in order to heat or cool the respective fluid to be used, if required. Furthermore, of course, the use of air as the fluid for generating the fluid flow for heating or cooling is to be understood only by way of example. Thus, for example, even in the embodiment variants of fig. 1 or 2, process gases, in particular inert process gases, can be used.

For example, with the embodiment variant shown, a melt layer process using PA66GF35 can be easily and efficiently implemented. Here, on the one hand (depending on the requirements relating to the design to be produced and/or due to material constraints) the previously applied printing material 50 can be actively warmed using hot (hot at about 150 ℃) air in order to achieve good adhesion, but on the other hand, for example in the case of sections of the component having a small cross section and/or a small wall thickness, it is also provided for the just applied printing material 51 to be cooled in order to prevent this printing material 51 from flowing away or melting. In this case, the temperature control device 4 integrates corresponding heating and cooling of components in the region of the printing nozzle 10 and thus on the print head of the 3D printing device, for example, in the embodiment according to fig. 2, by means of a plurality of

carriers

41, 42, 43 which each have a plurality of outflow openings 41a to 41e, 42a to 42e and which are annularly surrounded by the printing nozzle 10.

List of reference numerals

13D printing apparatus

10 printing nozzle

2 printing platform

3 sensing device

4 temperature regulating device

40 control electronic device

41. 42, 43 vectors

41a-41e outflow opening/emitter (temperature regulating element)

42a-42e outflow opening/emitter (temperature regulating element)

43a-43e outflow opening/emitter (temperature regulating element)

4a laser

400 multi-way valve

50. 51 printing material

R direction of application

Claims

A3D printing device having at least one printing nozzle (10) for applying printing material (50, 51) arranged for manufacturing a component to be printed in layers along an application direction (R),

it is characterized in that the preparation method is characterized in that,

the 3D printing device (1) has a temperature control device (4) which is set up and arranged to cool and heat the printing material (50, 51) that has been applied in the region of the printing nozzle (10).
2. 3D printing device according to claim 1, wherein the temperature regulating means (4) is set up and arranged for heating already applied printing material (50) located in the application direction (R) onto which new printing material is to be applied by the printing nozzle (10).
3.3D printing device according to claim 1 or 2, characterized in that the temperature regulating means (4) is set up and arranged for cooling a printing material (51) applied by the printing nozzle (10) after the application of the printing material (51) by the printing nozzle.
4. The 3D printing apparatus according to any of claims 1 to 3, characterized in that for heating and/or cooling the applied printing material (50, 51) at least one fluid flow with heated or cooled fluid can be generated via the temperature regulating device (4).
5. The 3D printing apparatus according to claim 4, characterized in that the temperature regulating device (4) has at least one carrier (41, 42, 43) with at least one outflow opening (41a-41e, 42a-42e, 43a-43e) for fluid.
6. The 3D printing device according to claim 5, characterized in that on the at least one carrier (41, 42, 43) there is at least one first outflow opening (41a-41e) for generating a fluid flow arranged for heating the printing material (50) and at least one second outflow opening (41a-41e) for generating a fluid flow arranged for cooling the printing material (50).
7. The 3D printing apparatus according to claim 5 or 6, characterized in that the temperature adjustment device (4) has at least two carriers (41, 42, 43).
8. The 3D printing device according to claim 7, characterized in that different carriers (41, 42, 43) are provided on the 3D printing device for generating different fluid flows and/or for different fluids.
9. The 3D printing apparatus according to any of claims 4 to 8, characterized in that the temperature regulating device (4) has at least one valve (400) for controlling the inflow of different fluids and/or for controlling the inflow of fluids via different fluid paths.
10. The 3D printing device according to claim 9, characterized in that the temperature regulating means (4) with the at least one valve (400) is set up and arranged to control the inflow of heated fluid via a different fluid path than the inflow of cooled fluid.
11. The 3D printing apparatus according to any of the preceding claims, characterized in that the temperature regulating device (4) has at least one emitter (41a-41e, 42a-42e, 43a-43e) for heating the printing material (50) that has been applied.
12. The 3D printing apparatus according to any of the preceding claims, wherein the temperature adjustment device (4) has control electronics (40) configured to control heating or cooling in dependence on the application direction (R) to which the printing nozzle (10) is adjusted.
3D printing device having at least one printing nozzle (10) for applying printing material (50, 51) arranged for manufacturing a component to be printed in layers along an application direction (R),

it is characterized in that the preparation method is characterized in that,

the 3D printing device has a temperature control device (4) having a plurality of temperature control elements (41a-41 e; 41a-42 e; 43a-43e) which are provided for cooling the printing material (50, 51) which has been applied and/or a plurality of temperature control elements (41a-41 e; 41a-42 e; 43a-43e) which are provided for heating the printing material (50, 51) which has been applied, wherein the temperature control elements (41a-41 e; 41a-42 e; 43a-43e) are arranged on a section of a carrier (41, 42, 43) of the temperature control device (4) which extends at least partially around the printing nozzle (10).
14. The 3D printing apparatus according to claim 13, characterized in that the temperature adjustment device (4) has control electronics (40) configured to utilize different temperature adjustment elements (41a-41 e; 41a-42 e; 43a-43e) depending on which application direction (R) the printing nozzle (10) is adjusted to.